Steam boiler



May Z4, E. KIDWELL STEAM BO ILER Filed DeoA, 1923 Patented lil'lay 242i,

nairsnsTA-Tes EDGAR KIDWELL, OF MILWAUKEE, WISCONSIN, ASSIlVSrNOllEtv T0 KIDWEL'L BOILER COM:L4

PANY, OF MILWAUKEE, VISCONSIN, A CORPORATION OF WISCONSIN.

STEAM BOILER.

Application flied December 4, 1923. serial No. 678,408.

This invention relates to steam boilers of the series tube and drum type, having' especial reference to a modification ot or improvement in the supplemental water circulation path or" the boiler forming the sub- `iect ot Letters Patent of the Unit-ed States No. 1.4112433 dated January 16, 1923, which. supplemental path and the main water circulation path of the boiler are so co-ordinated that the true lev-el et the boiler water is maintained within the steam-discharge drum. v

According to my present invention one ot the tube connections ot the supplemental. path is inclined to effect an upwa 1d curr-cnt or flow of water from one steamand-water 4drum to the other steunend-water drum, andthe other tube connection ot said path is horizontally disposed and so arranged as to permit the' water which tlows through the inclined tube to return to thedruin trom which it originated, and to effect and maintain a substantially equal level ot the water in the two drums, as will be hereinatter described and claimed.

The annexed drawing illustrates a longitudinal vertical section ot a water-tube boiler embodying my invention. In this boiler the main water circulating path comprises an upper rear steam-and-water drum a lower mud drinn 6, and aV orjard water drum 7 on a plane between thevdrums 5, 6, all said drums being connected in succeeding order by banks of tubes 8, 9 and 10.

The steam space ot the drum 5 is connected` by means oit overcomer or superheater tubes 11 with theV .steam space oli an upper forward stean'i-and-water drum 12, whereby the steam which is disengaged from the water in the drum 5 passes over to the steam spa-ce of the drum 12, whence it is withdrawn for service. yThe water spaces ot the drums 5 and 12 are connected by means of horizontal and inclined tubes 13, 1a, respectively, which are located in the heating zone ot the furnace, which tubes, together with the drum 12, provide supplemental circulation path into and through which a relatively small portion ot the water is diverted from the main path ot circulation in such manner as to maintain in the drum 12 a volume of water at substantially the same level as the water in the drum 5.

In the present instance the horizontal 'tube or tubes 13 are arranged in a plane below the level of the water in the drum 5 so as to permit the free flow of the waterirom the disengaging drum to the drinn 12, and the inclined tube or tubes 14 are arranged to eiect a forced rearward and upward yflow ot' the water from the drum 12 to the disengaging drum 5; the cross-sectional area ot the horizontal tube or tubes 13 being such as to equalize the influx and el'lluX ot water into and from thedrum 5 with a difference of water level or head in drinn 5 above that in drum 12 so small as to be negligible, thus maintaininga practically uniform volumnal flow of water through the supplement-al path and insuring` a substantially equal level ot the water in the two drums. In other words, steam formed in the horizontal tubes 18 does not serve to create a current or flow in any definite direction, whereas the steam gen# erated in the inclined tubes 14 causes a forced flow to the drum 5. Hence unless the crosssectional area ot the tubes 13 be such in relation to that of the tubes 14 as to accommodate the forced intlx of water into the drum 5, the water in the latter will stand higher than that in the drum 12 to an extent necessary to give the head required to force the water through the tubes 13 to the drum 12, and consequently the water in the drums will not be maintained at substantially the same level.

Vhile in the form of my invention herein illustrated the tube connection 14 is inclined to cause a water flow from the forward to the rearward steam-an'd-water drum, yet it is to be understood that, in pursuance of the principle of the invention, the inclination of such connection may be reversed to effect a flow from the rearward to the forward drum.

I claim 1. A steam boiler having a continuous main water circulation path and a supplemental water circulation path, said main path` including` a steam-and-water receptacle wherein the steam is disengaged from the water, and said supplemental path comprising a steam-and-water receptacle 'from which the steam is discharged, said latter receptacle being outside the main path of circulation, and said supplemental path also comprising two tube connections between the water spaces of the two receptacles, one ot said connections being inclined upwardly in its path from one receptacle to the other, and the other connection being horizontally disposed between the two steam and Water receptacles and being of such cross-sectional area as to permit the How from said other to said one receptacle of a Volume ot Water Substantially equal to that ot' the forced iow of Water through the inclined connection.A

A steam boiler havinga rear transverse steam-and-Water drum, a front 'ater drum, a rear mnd drum` banks of tubes successively connecting the said drums, a Viront steamand-.water drum, supplemental circnlatioi'i tube connections between the Water spaces oi' the steam-and-Water drums, one of said connections being horizontall)v disposed 'trom one steam and Water drinn to the other and the other of said connections being inclined upwardl from one drum to the other and being ot such cross-sectional area as to permit the How from aid other to d one drum oi av Volume of water substantiall7 equal to that of the forced flow ol water through the inclined connection.

3. A steam boiler having a rear transverse steam-and-Water drum, a rear mud drum, banks of tubes successively connecting the said drums, a itront steam-and-Water drum, supplemental circulation tube connections between the Water spaces of the steam-and- Water drums, one of said connections being' horizontally disposed from one steam and Water drum to the other and the other of said connections being` inclined upwardly from the Afront steam-and-Water drum to the rear steam-and-Water drinn, the cross-sectional area ot the horizontal connection being such as to permit the flow from the rear to the front steam-and--Water drinn of a volume of water substantially equal to that ot the forced flow of water through the inclined connection from the front to the rear steam-and-Water drinn.

Signed at Milwaukee, in the count7 of `Milwaukee and State of lVisconsin., this 30th 

